1
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Yang Y, Shao YT, Lu X, Yang Y, Ko HY, DiStasio RA, DiSalvo FJ, Muller DA, Abruña HD. Elucidating Cathodic Corrosion Mechanisms with Operando Electrochemical Transmission Electron Microscopy. J Am Chem Soc 2022; 144:15698-15708. [PMID: 35976815 DOI: 10.1021/jacs.2c05989] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cathodic corrosion represents an enigmatic electrochemical process in which metallic electrodes corrode under sufficiently reducing potentials. Although discovered by Fritz Haber in the 19th century, only recently has progress been made in beginning to understand the atomistic mechanisms of corroding bulk electrodes. The creation of nanoparticles as the end-product of the corrosion process suggests an additional length scale of complexity. Here, we studied the dynamic evolution of morphology, composition, and crystallographic structural information of nanocrystal corrosion products by analytical and four-dimensional electrochemical liquid-cell scanning transmission electron microscopy (EC-STEM). Our operando/in situ electron microscopy revealed, in real-time, at the nanometer scale, that cathodic corrosion yields significantly higher levels of structural degradation for heterogeneous nanocrystals than bulk electrodes. In particular, the cathodic corrosion of Au nanocubes on bulk Pt electrodes led to the unexpected formation of thermodynamically immiscible Au-Pt alloy nanoparticles. The highly kinetically driven corrosion process is evidenced by the successive anisotropic transition from stable Pt(111) bulk single-crystal surfaces evolving to energetically less-stable (100) and (110) steps. The motifs identified in this microscopy study of cathodic corrosion of nanocrystals are likely to underlie the structural evolution of nanoscale electrocatalysts during many electrochemical reactions under highly reducing potentials, such as CO2 and N2 reduction.
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Affiliation(s)
- Yao Yang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Yu-Tsun Shao
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
| | - Xinyao Lu
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Yan Yang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Hsin-Yu Ko
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Robert A DiStasio
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Francis J DiSalvo
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - David A Muller
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States.,Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Héctor D Abruña
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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2
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Yang Y, Peltier CR, Zeng R, Schimmenti R, Li Q, Huang X, Yan Z, Potsi G, Selhorst R, Lu X, Xu W, Tader M, Soudackov AV, Zhang H, Krumov M, Murray E, Xu P, Hitt J, Xu L, Ko HY, Ernst BG, Bundschu C, Luo A, Markovich D, Hu M, He C, Wang H, Fang J, DiStasio RA, Kourkoutis LF, Singer A, Noonan KJT, Xiao L, Zhuang L, Pivovar BS, Zelenay P, Herrero E, Feliu JM, Suntivich J, Giannelis EP, Hammes-Schiffer S, Arias T, Mavrikakis M, Mallouk TE, Brock JD, Muller DA, DiSalvo FJ, Coates GW, Abruña HD. Electrocatalysis in Alkaline Media and Alkaline Membrane-Based Energy Technologies. Chem Rev 2022; 122:6117-6321. [PMID: 35133808 DOI: 10.1021/acs.chemrev.1c00331] [Citation(s) in RCA: 75] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Hydrogen energy-based electrochemical energy conversion technologies offer the promise of enabling a transition of the global energy landscape from fossil fuels to renewable energy. Here, we present a comprehensive review of the fundamentals of electrocatalysis in alkaline media and applications in alkaline-based energy technologies, particularly alkaline fuel cells and water electrolyzers. Anion exchange (alkaline) membrane fuel cells (AEMFCs) enable the use of nonprecious electrocatalysts for the sluggish oxygen reduction reaction (ORR), relative to proton exchange membrane fuel cells (PEMFCs), which require Pt-based electrocatalysts. However, the hydrogen oxidation reaction (HOR) kinetics is significantly slower in alkaline media than in acidic media. Understanding these phenomena requires applying theoretical and experimental methods to unravel molecular-level thermodynamics and kinetics of hydrogen and oxygen electrocatalysis and, particularly, the proton-coupled electron transfer (PCET) process that takes place in a proton-deficient alkaline media. Extensive electrochemical and spectroscopic studies, on single-crystal Pt and metal oxides, have contributed to the development of activity descriptors, as well as the identification of the nature of active sites, and the rate-determining steps of the HOR and ORR. Among these, the structure and reactivity of interfacial water serve as key potential and pH-dependent kinetic factors that are helping elucidate the origins of the HOR and ORR activity differences in acids and bases. Additionally, deliberately modulating and controlling catalyst-support interactions have provided valuable insights for enhancing catalyst accessibility and durability during operation. The design and synthesis of highly conductive and durable alkaline membranes/ionomers have enabled AEMFCs to reach initial performance metrics equal to or higher than those of PEMFCs. We emphasize the importance of using membrane electrode assemblies (MEAs) to integrate the often separately pursued/optimized electrocatalyst/support and membranes/ionomer components. Operando/in situ methods, at multiscales, and ab initio simulations provide a mechanistic understanding of electron, ion, and mass transport at catalyst/ionomer/membrane interfaces and the necessary guidance to achieve fuel cell operation in air over thousands of hours. We hope that this Review will serve as a roadmap for advancing the scientific understanding of the fundamental factors governing electrochemical energy conversion in alkaline media with the ultimate goal of achieving ultralow Pt or precious-metal-free high-performance and durable alkaline fuel cells and related technologies.
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Affiliation(s)
- Yao Yang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Cheyenne R Peltier
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Rui Zeng
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Roberto Schimmenti
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Qihao Li
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Xin Huang
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
| | - Zhifei Yan
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Georgia Potsi
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Ryan Selhorst
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Xinyao Lu
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Weixuan Xu
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Mariel Tader
- Department of Physics, Cornell University, Ithaca, New York 14853, United States
| | - Alexander V Soudackov
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Hanguang Zhang
- Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Mihail Krumov
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Ellen Murray
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Pengtao Xu
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Jeremy Hitt
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Linxi Xu
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Hsin-Yu Ko
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Brian G Ernst
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Colin Bundschu
- Department of Physics, Cornell University, Ithaca, New York 14853, United States
| | - Aileen Luo
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Danielle Markovich
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
| | - Meixue Hu
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Cheng He
- Chemical and Materials Science Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Hongsen Wang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Jiye Fang
- Department of Chemistry, State University of New York at Binghamton, Binghamton, New York 13902, United States
| | - Robert A DiStasio
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Lena F Kourkoutis
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States.,Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Andrej Singer
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Kevin J T Noonan
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Li Xiao
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Lin Zhuang
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Bryan S Pivovar
- Chemical and Materials Science Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Piotr Zelenay
- Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Enrique Herrero
- Instituto de Electroquímica, Universidad de Alicante, Alicante E-03080, Spain
| | - Juan M Feliu
- Instituto de Electroquímica, Universidad de Alicante, Alicante E-03080, Spain
| | - Jin Suntivich
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States.,Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Emmanuel P Giannelis
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | | | - Tomás Arias
- Department of Physics, Cornell University, Ithaca, New York 14853, United States
| | - Manos Mavrikakis
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Thomas E Mallouk
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Joel D Brock
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
| | - David A Muller
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States.,Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Francis J DiSalvo
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Geoffrey W Coates
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Héctor D Abruña
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States.,Center for Alkaline Based Energy Solutions (CABES), Cornell University, Ithaca, New York 14853, United States
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3
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Zeng R, Yang Y, Feng X, Li H, Gibbs LM, DiSalvo FJ, Abruña HD. Nonprecious transition metal nitrides as efficient oxygen reduction electrocatalysts for alkaline fuel cells. Sci Adv 2022; 8:eabj1584. [PMID: 35108056 PMCID: PMC8809680 DOI: 10.1126/sciadv.abj1584] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 12/01/2021] [Indexed: 06/14/2023]
Abstract
Hydrogen fuel cells have attracted growing attention for high-performance automotive power but are hindered by the scarcity of platinum (and other precious metals) used to catalyze the sluggish oxygen reduction reaction (ORR). We report on a family of nonprecious transition metal nitrides (TMNs) as ORR electrocatalysts in alkaline medium. The air-exposed nitrides spontaneously form a several-nanometer-thick oxide shell on the conductive nitride core, serving as a highly active catalyst architecture. The most active catalyst, carbon-supported cobalt nitride (Co3N/C), exhibited a half-wave potential of 0.862 V and achieved a record-high peak power density among reported nitride cathode catalysts of 700 mW cm-2 in alkaline membrane electrode assemblies. Operando x-ray absorption spectroscopy studies revealed that Co3N/C remains stable below 1.0 V but experiences irreversible oxidation at higher potentials. This work provides a comprehensive analysis of nonprecious TMNs as ORR electrocatalysts and will help inform future design of TMNs for alkaline fuel cells and other energy applications.
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4
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Beaucage PA, van Dover RB, DiSalvo FJ, Gruner SM, Wiesner U. Superconducting Quantum Metamaterials from Convergence of Soft and Hard Condensed Matter Science. Adv Mater 2021; 33:e2006975. [PMID: 33998066 DOI: 10.1002/adma.202006975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 02/17/2021] [Indexed: 06/12/2023]
Abstract
Superconducting quantum metamaterials are expected to exhibit a variety of novel properties, but have been a major challenge to prepare as a result of the lack of appropriate synthetic routes to high-quality materials. Here, the discovery of synthesis routes to block copolymer (BCP) self-assembly-directed niobium nitrides and carbonitrides is described. The resulting materials exhibit unusual structure retention even at temperatures as high as 1000 °C and resulting critical temperature, Tc , values comparable to their bulk analogues. Applying the concepts of soft matter self-assembly, it is demonstrated that a series of four different BCP-directed mesostructured superconductors are accessible from a single triblock terpolymer. Resulting materials display a mesostructure-dependent Tc without substantial variation of the XRD-measured lattice parameters. Finally, field-dependent magnetization measurements of a sample with double-gyroid morphology show abrupt jumps comparable in overall behavior to flux avalanches. Results suggest a fruitful convergence of soft and hard condensed matter science.
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Affiliation(s)
- Peter A Beaucage
- Materials Science & Engineering Department, Cornell University, Ithaca, NY, 14853, USA
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
- Materials Science & Engineering Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA
| | - R Bruce van Dover
- Materials Science & Engineering Department, Cornell University, Ithaca, NY, 14853, USA
| | | | - Sol M Gruner
- Physics Department, Cornell University, Ithaca, NY, 14853, USA
- Cornell High Energy Synchrotron Source, Cornell University, Ithaca, NY, 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY, 14853, USA
| | - Ulrich Wiesner
- Materials Science & Engineering Department, Cornell University, Ithaca, NY, 14853, USA
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5
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Yuan Y, Adimi S, Thomas T, Wang J, Guo H, Chen J, Attfield JP, DiSalvo FJ, Yang M. Co 3Mo 3N-An efficient multifunctional electrocatalyst. Innovation (N Y) 2021; 2:100096. [PMID: 34557748 PMCID: PMC8454690 DOI: 10.1016/j.xinn.2021.100096] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Accepted: 03/12/2021] [Indexed: 11/21/2022] Open
Abstract
Efficient catalysts are required for both oxidative and reductive reactions of hydrogen and oxygen in sustainable energy conversion devices. However, current precious metal-based electrocatalysts do not perform well across the full range of reactions and reported multifunctional catalysts are all complex hybrids. Here, we show that single-phase porous Co3Mo3N prepared via a facile method is an efficient and reliable electrocatalyst for three essential energy conversion reactions; oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and hydrogen evolution reaction (HER) in alkaline solutions. Co3Mo3N presents outstanding OER, ORR, and HER activity with high durability, comparable with the commercial catalysts RuO2 for OER and Pt/C for ORR and HER. In practical demonstrations, Co3Mo3N gives high specific capacity (850 mA h gZn−1 at 10 mA cm−2) as the cathode in a zinc-air battery, and a low potential (1.63 V at 10 mA cm−2) used in a water-splitting electrolyzer. Availability of Co and Mo d-states appear to result in high ORR and HER performance, while the OER properties result from a cobalt oxide-rich activation surface layer. Our findings will inspire further development of bimetallic nitrides as cost-effective and versatile multifunctional catalysts that will enable scalable usage of electrochemical energy devices. Porous Co3Mo3N can act as a multifunctional electrocatalyst for OER, ORR, and HER Co3Mo3N performs better than precious metal catalysts Cobalt oxide-rich activation surface layer is shown to aid OER activity Better ORR and HER performance of Co3Mo3N is due to Co and Mo d-states
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Affiliation(s)
- Yao Yuan
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China.,Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - Samira Adimi
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China
| | - Tiju Thomas
- Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras Adyar, Chennai 600036, Tamil Nadu, India
| | - Jiacheng Wang
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Haichuan Guo
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China
| | - Jian Chen
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China
| | - J Paul Attfield
- Centre for Science at Extreme Conditions and School of Chemistry, University of Edinburgh, Edinburgh, EH9 3JZ, UK
| | - Francis J DiSalvo
- Department of Chemistry and Chemical Biology, Cornell University, New York, 14853, USA
| | - Minghui Yang
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, China
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6
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Yang Y, Xiong Y, Zeng R, Lu X, Krumov M, Huang X, Xu W, Wang H, DiSalvo FJ, Brock JD, Muller DA, Abruña HD. Operando Methods in Electrocatalysis. ACS Catal 2021. [DOI: 10.1021/acscatal.0c04789] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Yao Yang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Yin Xiong
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Rui Zeng
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Xinyao Lu
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Mihail Krumov
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Xin Huang
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
- Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, New York 14853, United States
| | - Weixuan Xu
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Hongsen Wang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Francis J. DiSalvo
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Joel. D. Brock
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
- Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, New York 14853, United States
| | - David A. Muller
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
- Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, United States
| | - Héctor D. Abruña
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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7
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Hesse SA, Fritz KE, Beaucage PA, Thedford RP, Yu F, DiSalvo FJ, Suntivich J, Wiesner U. Materials Combining Asymmetric Pore Structures with Well-Defined Mesoporosity for Energy Storage and Conversion. ACS Nano 2020; 14:16897-16906. [PMID: 33237717 DOI: 10.1021/acsnano.0c05903] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Porous materials design often faces a trade-off between the requirements of high internal surface area and high reagent flux. Inorganic materials with asymmetric/hierarchical pore structures or well-defined mesopores have been tested to overcome this trade-off, but success has remained limited when the strategies are employed individually. Here, the attributes of both strategies are combined and a scalable path to porous titanium nitride (TiN) and carbon membranes that are conducting (TiN, carbon) or superconducting (TiN) is demonstrated. These materials exhibit a combination of asymmetric, hierarchical pore structures and well-defined mesoporosity throughout the material. Fast transport through such TiN materials as an electrochemical double-layer capacitor provides a substantial improvement in capacity retention at high scan rates, resulting in state-of-the-art power density (28.2 kW kg-1) at competitive energy density (7.3 W-h kg-1). In the case of carbon membranes, a record-setting power density (287.9 kW kg-1) at 14.5 W-h kg-1 is reported. Results suggest distinct advantages of such pore architectures for energy storage and conversion applications and provide an advanced avenue for addressing the trade-off between high-surface-area and high-flux requirements.
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Affiliation(s)
- Sarah A Hesse
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Kevin E Fritz
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Peter A Beaucage
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - R Paxton Thedford
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
- Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Fei Yu
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Francis J DiSalvo
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Jin Suntivich
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
- Kavli Institute for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Ulrich Wiesner
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
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8
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Xiong Y, Yang Y, DiSalvo FJ, Abruña HD. Synergistic Bimetallic Metallic Organic Framework-Derived Pt-Co Oxygen Reduction Electrocatalysts. ACS Nano 2020; 14:13069-13080. [PMID: 32935972 DOI: 10.1021/acsnano.0c04559] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The rational design of Pt-based electrocatalysts is of paramount importance for the commercialization of proton exchange membrane fuel cells (PEMFCs). Pt-Co alloys and nitrogen-doped carbons have been shown to be effective in enhancing the kinetics of the oxygen reduction reaction (ORR). Herein, we reported on two kinds of Pt-Co electrocatalysts, PtCo ordered intermetallic and PtCo2 disordered alloys, supported on bimetallic MOF-derived N-doped carbon. The synergistic interaction between Pt-Co nanoparticles and Co-N-C enhanced the overall ORR activity and maintained the integrity of both structures and their electrochemical properties during long-term stability testing. The optimal activity for both PtCo and PtCo2 occurred after 20 000 potential cycles. The enhanced performance of PtCo was ascribed to the formation of a two-atomic-layer Pt-rich shell and the lattice strain caused by the core-shell PtCo@Pt structure. The increased activity of PtCo2 was ascribed to the formation of large, spongy, and small solid nanoparticles during electrochemical dealloying and thus the exposure of more Pt sites on the surface. The strategy described herein advances our understanding of the structure-activity relationship in electrocatalysis and sheds light on the future development of more active and durable ORR electrocatalysts.
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Affiliation(s)
- Yin Xiong
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - Yao Yang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - Francis J DiSalvo
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - Héctor D Abruña
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
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9
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Lu X, Ahmadi M, DiSalvo FJ, Abruña HD. Enhancing the Electrocatalytic Activity of Pd/M (M = Ni, Mn) Nanoparticles for the Oxygen Reduction Reaction in Alkaline Media through Electrochemical Dealloying. ACS Catal 2020. [DOI: 10.1021/acscatal.9b05499] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xinyao Lu
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Mahdi Ahmadi
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Francis J. DiSalvo
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Héctor D. Abruña
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
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10
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Affiliation(s)
- Hongsen Wang
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Yao Yang
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Francis J. DiSalvo
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Héctor D. Abruña
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
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11
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Yang Y, Chen G, Zeng R, Villarino AM, DiSalvo FJ, van Dover RB, Abruña HD. Combinatorial Studies of Palladium-Based Oxygen Reduction Electrocatalysts for Alkaline Fuel Cells. J Am Chem Soc 2020; 142:3980-3988. [DOI: 10.1021/jacs.9b13400] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yao Yang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Guanyu Chen
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Rui Zeng
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Andrés Molina Villarino
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Francis J. DiSalvo
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - R. Bruce van Dover
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Héctor D. Abruña
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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12
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Abstract
Abstract
The compound Cs[OCN] has been synthesized and its crystal structure and Raman spectrum were determined on selected single crystals. As postulated in earlier work, the title compound crystallizes isopointal to KN3 exhibiting the space group I4/mcm (no. 140, Z = 4) with the lattice parameters a = 653.79(2) and c = 799.42(5) pm. The Raman spectrum verified the nature of the triatomic moiety and shows the frequencies typical for an [OCN]− anion with Fermi resonance between the 2δ and the ν
sym vibrations. The undisturbed frequencies and the resulting force constants have been calculated and compared to those of other alkali metal compounds containing comparable linear triatomic anions.
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory, Department of Chemistry and Chemical Biology , Cornell University , Ithaca, NY 14853-1301 , USA
| | - Armin Schulz
- Max-Planck-Institut für Festkörperforschung , Heisenbergstraße 1 , D-70569 Stuttgart , Germany
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology , Cornell University , Ithaca, NY 14853-1301 , USA
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13
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Affiliation(s)
- Yao Yang
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Rui Zeng
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Yin Xiong
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Francis J. DiSalvo
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Héctor D. Abruña
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
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14
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Ren D, Padgett E, Yang Y, Shen L, Shen Y, Levin BDA, Yu Y, DiSalvo FJ, Muller DA, Abruña HD. Ultrahigh Rate Performance of a Robust Lithium Nickel Manganese Cobalt Oxide Cathode with Preferentially Orientated Li-Diffusing Channels. ACS Appl Mater Interfaces 2019; 11:41178-41187. [PMID: 31600433 DOI: 10.1021/acsami.9b05602] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Lithium nickel manganese cobalt oxide (NMC) materials, with low cost and high energy density, are considered to be among the most promising cathode materials for Li-ion batteries (LIBs). However, several issues have hindered their further deployment, particularly for high-powered applications, including limited rate capability, capacity loss during cycling (especially at high temperatures and high voltages), and difficulty in reproducibly preparing the desired particle morphology. In this work, we have developed a robust LiNi0.33Mn0.33Co0.33O2 cathode material (NMC-111) capable of high-rate performance for LIBs. Our high power NMC-111 (HP-NMC) cathode materials showed significantly enhanced electrochemical performance, relative to a commercial NMC-111 (c-NMC), with discharge capacities of 138 and 131 mAh/g at high current rates of 20 and 30 C, respectively. The material also exhibited enhanced cycling stability under both room temperature and at 50 °C. We ascribe the high performance of our material to a unique crystalline microstructure observed by electron microscopy characterization, which showed preferential orientation of the Li-diffusing channels radially outward. This HP-NMC material achieved one of the highest performance metrics among NMC materials reported to date, especially for high-powered electric vehicles.
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Affiliation(s)
- Dong Ren
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853-1301 , United States
| | - Elliot Padgett
- School of Applied and Engineering Physics , Cornell University , Ithaca , New York 14853 , United States
| | - Yao Yang
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853-1301 , United States
| | - Luxi Shen
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853-1301 , United States
| | - Yun Shen
- Lionano, Inc. , 19 Presidential Way, Suite 103 , Woburn , Massachusetts 01801 , United States
| | - Barnaby D A Levin
- School of Applied and Engineering Physics , Cornell University , Ithaca , New York 14853 , United States
| | - Yingchao Yu
- Lionano, Inc. , 19 Presidential Way, Suite 103 , Woburn , Massachusetts 01801 , United States
| | - Francis J DiSalvo
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853-1301 , United States
| | - David A Muller
- School of Applied and Engineering Physics , Cornell University , Ithaca , New York 14853 , United States
| | - Héctor D Abruña
- Department of Chemistry and Chemical Biology, Baker Laboratory , Cornell University , Ithaca , New York 14853-1301 , United States
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15
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Xiong Y, Yang Y, DiSalvo FJ, Abruña HD. Metal–Organic-Framework-Derived Co–Fe Bimetallic Oxygen Reduction Electrocatalysts for Alkaline Fuel Cells. J Am Chem Soc 2019; 141:10744-10750. [DOI: 10.1021/jacs.9b03561] [Citation(s) in RCA: 138] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Yin Xiong
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Yao Yang
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Francis J. DiSalvo
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
| | - Héctor D. Abruña
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
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16
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Xiong Y, Yang Y, Feng X, DiSalvo FJ, Abruña HD. A Strategy for Increasing the Efficiency of the Oxygen Reduction Reaction in Mn-Doped Cobalt Ferrites. J Am Chem Soc 2019; 141:4412-4421. [DOI: 10.1021/jacs.8b13296] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yin Xiong
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - Yao Yang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - Xinran Feng
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
- Cornell High Energy Synchrotron Source (CHESS), Cornell University, Ithaca, New York 14850, United States
| | - Francis J. DiSalvo
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
| | - Héctor D. Abruña
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14850, United States
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17
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Haas CD, Fischer A, Hauf C, Wieser C, Schmidt AP, Eickerling G, Scheidt EW, Schiffmann JG, Reckeweg O, DiSalvo FJ, Rodewald UC, Pöttgen R, van Wüllen L, Scherer W. The Color of the Elements: A Combined Experimental and Theoretical Electron Density Study of ScB 2 C 2. Angew Chem Int Ed Engl 2019; 58:2360-2364. [PMID: 30570814 DOI: 10.1002/anie.201813102] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Indexed: 11/08/2022]
Abstract
The chemical or physical control parameters for the onset of superconductivity in MB2 C2 hetero-graphene materials are unclear. This is mainly due to the almost ubiquitous positional B/C disorder, rendering the description of real structures of borocarbides into one of the most challenging problems in materials science. We will show that high-resolution X-ray diffraction data provides all the essential information to decode even complex coloring problems due to B/C disorder. Electron density studies and subsequent analyses of the fine structure of the Laplacian of the electron density resolves the local electronic structure of ScB2 C2 at sub-atomic resolution and allows for an unequivocal identification of all atoms involved in the coloring scenario. This information could finally be used to identify the electron deficient character of the B/C layers in ScB2 C2 and to synthesize the first bimetallic hetero-metallocene with lithium and scandium atoms embedded in the pentagonal and heptagonal voids, respectively.
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Affiliation(s)
- Christof D Haas
- Institut für Physik, Universität Augsburg, 86135, Augsburg, Germany
| | - Andreas Fischer
- Institut für Physik, Universität Augsburg, 86135, Augsburg, Germany
| | - Christoph Hauf
- Institut für Physik, Universität Augsburg, 86135, Augsburg, Germany
| | - Christian Wieser
- Institut für Physik, Universität Augsburg, 86135, Augsburg, Germany
| | | | - Georg Eickerling
- Institut für Physik, Universität Augsburg, 86135, Augsburg, Germany
| | | | - Jan G Schiffmann
- Institut für Physik, Universität Augsburg, 86135, Augsburg, Germany
| | - Olaf Reckeweg
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853-1301, USA
| | - Francis J DiSalvo
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, 14853-1301, USA
| | - Ute C Rodewald
- Institut für Anorganische und Analytische Chemie, Universität Münster, 48149, Münster, Germany
| | - Rainer Pöttgen
- Institut für Anorganische und Analytische Chemie, Universität Münster, 48149, Münster, Germany
| | - Leo van Wüllen
- Institut für Physik, Universität Augsburg, 86135, Augsburg, Germany
| | - Wolfgang Scherer
- Institut für Physik, Universität Augsburg, 86135, Augsburg, Germany
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18
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Haas CD, Fischer A, Hauf C, Wieser C, Schmidt AP, Eickerling G, Scheidt EW, Schiffmann JG, Reckeweg O, DiSalvo FJ, Rodewald UC, Pöttgen R, van Wüllen L, Scherer W. The Color of the Elements: A Combined Experimental and Theoretical Electron Density Study of ScB2
C2. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201813102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Christof D. Haas
- Institut für Physik; Universität Augsburg; 86135 Augsburg Germany
| | - Andreas Fischer
- Institut für Physik; Universität Augsburg; 86135 Augsburg Germany
| | - Christoph Hauf
- Institut für Physik; Universität Augsburg; 86135 Augsburg Germany
| | - Christian Wieser
- Institut für Physik; Universität Augsburg; 86135 Augsburg Germany
| | | | - Georg Eickerling
- Institut für Physik; Universität Augsburg; 86135 Augsburg Germany
| | | | | | - Olaf Reckeweg
- Department of Chemistry and Chemical Biology; Cornell University; Ithaca NY 14853-1301 USA
| | - Francis J. DiSalvo
- Department of Chemistry and Chemical Biology; Cornell University; Ithaca NY 14853-1301 USA
| | - Ute C. Rodewald
- Institut für Anorganische und Analytische Chemie; Universität Münster; 48149 Münster Germany
| | - Rainer Pöttgen
- Institut für Anorganische und Analytische Chemie; Universität Münster; 48149 Münster Germany
| | - Leo van Wüllen
- Institut für Physik; Universität Augsburg; 86135 Augsburg Germany
| | - Wolfgang Scherer
- Institut für Physik; Universität Augsburg; 86135 Augsburg Germany
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19
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Gunji T, Wakabayashi RH, Noh SH, Han B, Matsumoto F, DiSalvo FJ, Abruña HD. The effect of alloying of transition metals (M = Fe, Co, Ni) with palladium catalysts on the electrocatalytic activity for the oxygen reduction reaction in alkaline media. Electrochim Acta 2018. [DOI: 10.1016/j.electacta.2018.06.051] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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20
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21
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Xiong Y, Yang Y, DiSalvo FJ, Abruña HD. Pt-Decorated Composition-Tunable Pd-Fe@Pd/C Core-Shell Nanoparticles with Enhanced Electrocatalytic Activity toward the Oxygen Reduction Reaction. J Am Chem Soc 2018; 140:7248-7255. [PMID: 29779380 DOI: 10.1021/jacs.8b03365] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Design of electrocatalysts with both a high-Pt-utilization efficiency and enhanced electrochemical activity is still the key challenge in the development of proton exchange membrane fuel cells. In the present work, Pd-Fe/C bimetallic nanoparticles (NPs) with an optimal Fe composition and decorated with Pt are introduced as promising catalysts toward the oxygen reduction reaction. These bimetallic nanoparticles have a Pd-Fe@Pd core-shell structure with a surface Pt decoration as established through the use of electron energy loss spectroscopy (EELS) and energy-dispersive X-ray (EDX) spectroscopy. These catalysts exhibit excellent electrocatalytic activity ( E1/2 = 0.866 V vs RHE), increasing the mass activity by more than 70% over that of Pt/C in terms of the total mass of Pt and Pd and by 14 times if only Pt is considered. Simple geometrical calculations, based on spherical core-shell models, indicate that Pd-Fe@Pt has a surface Pt decoration rather than a complete Pt monolayer. Such calculations applied to other examples in the literature point out the need for careful and rigorous arguments about claimed "Pt monolayer/multilayers". Such calculations must be based on not only elemental mapping data but also on the Pt/Pd and other metal atomic ratios in the precursors. Our analysis predicts a minimal Pt/Pd atomic ratio in order to achieve a complete Pt monolayer on the surface of the core materials.
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Affiliation(s)
- Yin Xiong
- Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14850 , United States
| | - Yao Yang
- Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14850 , United States
| | - Francis J DiSalvo
- Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14850 , United States
| | - Héctor D Abruña
- Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14850 , United States
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22
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Reckeweg O, Conrad M, Schulz A, DiSalvo FJ, Schleid T. Synthesis, vibrational spectra and single-crystal structure determination of lithium tricyanomethanide Li[C(CN)3]. Zeitschrift für Naturforschung B 2018. [DOI: 10.1515/znb-2017-0216] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The long-elusive structure of lithium tricyanomethanide Li[C(CN)3] has been determined on the basis of material synthesized via a metathesis reaction of Ag[C(CN)3] with LiCl in water driven by AgCl precipitation and subsequently recrystallization from methanol. Li[C(CN)3] crystallizes in the non-centrosymmetric orthorhombic space group Ima2 with the unit-cell parameters a=751.06(4), b=1059.75(6) and c=563.27(3) pm adopting a unique structure with planar [C(CN)3]− anions exhibiting nearly ideal trigonal planar D
3
h
symmetry. The Li+ cations are coordinated by five independent tricyanomethanide anions forming a distorted square pyramid with Li–N distances between 202 and 249 pm. The vibrational frequencies were also determined and along with other properties of Li[C(CN)3] compared with those of related compounds.
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Affiliation(s)
- Olaf Reckeweg
- Institut für Anorganische Chemie , Universität Stuttgart, Pfaffenwaldring 55 , D-70569 Stuttgart , Germany
- Baker Laboratory , Department of Chemistry and Chemical Biology , Cornell University , Ithaca, NY 14853-1301 , USA , Fax: +49-711-685-64241
| | - Maurice Conrad
- Institut für Anorganische Chemie , Universität Stuttgart, Pfaffenwaldring 55 , D-70569 Stuttgart , Germany
| | - Armin Schulz
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1 , D-70569 Stuttgart , Germany
| | - Francis J. DiSalvo
- Baker Laboratory , Department of Chemistry and Chemical Biology , Cornell University , Ithaca, NY 14853-1301 , USA
| | - Thomas Schleid
- Institut für Anorganische Chemie , Universität Stuttgart, Pfaffenwaldring 55 , D-70569 Stuttgart , Germany
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23
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Abstract
Abstract
Transparent-yellow single crystals of YbF2 were obtained as only crystalline product from the solid-state reaction of Yb and teflon designed to yield ‘Yb3C3F2’ in addition to some amorphous black material. The first single-crystal structure determination of YbF2 (cubic space group Fm3̅m, CaF2-type structure, a=559.46(16) pm; R1=1.2%, wR2=3.2%) was the starting point to compare isostructural binary fluorides MF2 and hydrides MH2 (M=Ca, Yb, Eu, Sr and Ba) exhibiting an as-yet unexplained small volume per formula unit for YbH2.
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory , Department of Chemistry and Chemical Biology , Cornell University , Ithaca, NY 14853-1301 , USA
| | - Francis J. DiSalvo
- Baker Laboratory , Department of Chemistry and Chemical Biology , Cornell University , Ithaca, NY 14853-1301 , USA
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24
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Affiliation(s)
- Peter M. Csernica
- Department
of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
| | - James R. McKone
- Department
of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | | | - William R. Dichtel
- Department
of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Héctor D. Abruña
- Department
of Chemistry and Chemical Biology, Cornell University, Ithaca New York 14853, United States
| | - Francis J. DiSalvo
- Department
of Chemistry and Chemical Biology, Cornell University, Ithaca New York 14853, United States
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25
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Reckeweg O, DiSalvo FJ. Oxide meets silicide – synthesis and single-crystal structure of Ca 21SrSi 24O 2. Zeitschrift für Naturforschung B 2017. [DOI: 10.1515/znb-2017-0022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
A few black, rectangular thin plates of Ca21SrSi24O2 were obtained by serendipity in a solid-state reaction of calcium metal, strontium chloride and silicon powder at 1200 K for 2 days designed to produce ‘Ca2SrCl2[Si3]’. The title compound forms next to some CaSi and some remaining educts. Ca21SrSi24O2 crystallizes in the monoclinic space group C2/m (no. 12) with unit cell parameters of a=1895.2(2), b=450.63(5) and c=1397.33(18) pm and β=112.008(7)° (Z=1). The title compound shows planar, eight-membered, kinked Si8 chains with Si–Si distances between 241.4 and 245.0 pm indicating bonding interactions and kinked ‘rope ladders’ connecting the chains with interatomic Si–Si distances in the range 268.1–274.7 pm. Embedded in between these silicon substructures are columns of oxygen centered, apex sharing [(Ca1−x
Sr
x
)6/2O] octahedra and calcium ions.
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA , Fax: +1-607-255-4137
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
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26
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Xiong FQ, Wan L, Li Y, Thomas T, DiSalvo FJ, Yang M. Crucial Role of Donor Density in the Performance of Oxynitride Perovskite LaTiO 2 N for Photocatalytic Water Oxidation. ChemSusChem 2017; 10:930-937. [PMID: 28093899 DOI: 10.1002/cssc.201601602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 12/28/2016] [Indexed: 06/06/2023]
Abstract
LaTiO2 N photocatalysts were prepared by thermal ammonolysis of flux-synthesized La2 Ti2 O7 and La2 TiO5 , and were investigated for water oxidation. Though LaTiO2 N derived from La2 TiO5 appears defect-free by UV/Vis/near-IR and electron paramagnetic resonance (EPR) spectroscopy, its performance is much lower than that of conventional La2 Ti2 O7 -derived LaTiO2 N with defects. It is shown by Mott-Schottky analysis that La2 TiO5 -derived LaTiO2 N has significantly lower donor density; this can result in insufficient built-in electric field for the separation of photogenerated electrons and holes. The lower donor density is also consistent with the smaller difference between the Fermi level and the valence-band maximum, which accounts for a lower oxidative power of the holes. In light of this discovery, the donor density was increased substantially by introducing anion vacancies through annealing in Ar. This resulted in improved performance. The CoOx -assisted La2 TiO5 -derived LaTiO2 N annealed at 713 °C has a higher quantum efficiency (25 %) at 450 nm than high-performance conventional CoOx /LaTiO2 N (21 %).
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Affiliation(s)
- Feng-Qiang Xiong
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P. R. China
| | - Lipeng Wan
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P. R. China
| | - Yue Li
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P. R. China
| | - Tiju Thomas
- Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai, 600036, Tamil Nadu, India
| | - Francis J DiSalvo
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, 14853-1301, USA
| | - Minghui Yang
- Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, P. R. China
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27
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Reckeweg O, Schulz A, DiSalvo FJ. Synthesis, crystal structure and Raman spectrum of Ba 7[BO 3] 3Br(O 1.33F 1.33). Zeitschrift für Naturforschung B 2017. [DOI: 10.1515/znb-2016-0243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
In addition to amorphous material and Ba7[BO3]4−x
F2−3x
, air and moisture sensitive single crystals of Ba7[BO3]3Br(O1.33F1.33) were formed from H3BO3, Ba(OH)2, BaF2 and BaBr2·2 H2O in alumina crucibles open to the atmosphere at 1300 K for 13 h. Ba7[BO3]3Br(O1.33F1.33) crystallizes in the hexagonal space group P63
mc (no. 186, Z=2) with the lattice parameters a=1118.1(2) and c=723.93(13) pm. The Raman spectrum of the title compounds was also acquired and is compared to literature data.
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA , Fax:+1-607-255-4137
| | - Armin Schulz
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
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28
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Reckeweg O, Schulz A, DiSalvo FJ. Synthesis, single-crystal structure determination and Raman spectrum of Ca 2.57(4)Sr 0.43(4)Cl 2[CBN]. Zeitschrift für Naturforschung B 2017. [DOI: 10.1515/znb-2016-0258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractSolid-state reaction of Ca, CaCl2, Sr, SrCl2, C and BN at 900°C for 3 days yielded transparent red needles of Ca2.57(4)Sr0.43(4)Cl2[CBN] as minority product (<10%) mixed with crystals of isotypic yellow Ca3Cl2[CBN] and orange Sr3Cl2[CBN]. Ca2.57(4)Sr0.43(4)Cl2[CBN] crystallizes in the space groupPnma(no.62) with the unit cell parameters ofa=1389.2(6),b=386.05(15) andc=1131.2(4)pm (Z=4). The Raman spectrum confirms the presence of the [CBN]4−unit. The incremental volume of the [CBN]4−is calculated to be 50.7(10)Å3.
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA , Fax: +1-607-255-4137
| | - Armin Schulz
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
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29
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Abstract
Extensive efforts to develop highly active and strongly durable electrocatalyst for oxygen reduction are motivated by a need for metal-air batteries and fuel cells. Here, we report a very promising catalyst prototype of structurally ordered Pd-based alloys, Pd3Pb intermetallic compound. Such structurally ordered Pd3Pb/C exhibits a significant increase in mass activity. More importantly, compared to the conventional Pt/C catalysts, ordered Pd3Pb/C is highly durable and exhibits a much longer cycle life and higher cell efficiency in Zn-air batteries. Interestingly, ordered Pd3Pb/C possesses very high methanol tolerance during electrochemical oxygen reduction, which make it an excellent methanol-tolerant cathode catalyst for alkaline polymer electrolyte membrane fuel cells. This study provides a promising route to optimize the synthesis of ordered Pd-based intermetallic catalysts for fuel cells and metal-air batteries.
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Affiliation(s)
- Zhiming Cui
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853-1301, United States
| | - Hao Chen
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853-1301, United States
| | - Mengtian Zhao
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853-1301, United States
| | - Francis J DiSalvo
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853-1301, United States
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30
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Reckeweg O, Schulz A, DiSalvo FJ. Synthesis, single-crystal structure determination and Raman spectra of the tricyanomelaminates Na A
5[C 6N 9] 2 · 4 H 2O ( A = Rb, Cs). Zeitschrift für Naturforschung B 2016. [DOI: 10.1515/znb-2016-0024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Transparent colorless crystals of NaA
5[C6N9]2 · 4 H2O (A = Rb, Cs) were obtained by blending aqueous solutions of Na3[C6N9] and RbF or CsF, respectively, and subsequent evaporation of the water under ambient conditions. Both compounds crystallize in the space group P21/m (no. 11) with the cell parameters a = 815.56(16), b = 1637.7(4) and c = 1036.4(3) pm, and β = 110.738(12)° for NaRb5[C6N9]2 · 4 H2O and a = 843.32(6), b = 1708.47(11) and c = 1052.42(7) pm, and β = 112.034(2)° for NaCs5[C6N9]2 · 4 H2O, respectively. Raman spectra of the title compounds complement our results.
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
| | - Armin Schulz
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
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31
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Robbins SW, Beaucage PA, Sai H, Tan KW, Werner JG, Sethna JP, DiSalvo FJ, Gruner SM, Van Dover RB, Wiesner U. Block copolymer self-assembly-directed synthesis of mesoporous gyroidal superconductors. Sci Adv 2016; 2:e1501119. [PMID: 27152327 PMCID: PMC4846463 DOI: 10.1126/sciadv.1501119] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 11/24/2015] [Indexed: 05/19/2023]
Abstract
Superconductors with periodically ordered mesoporous structures are expected to have properties very different from those of their bulk counterparts. Systematic studies of such phenomena to date are sparse, however, because of a lack of versatile synthetic approaches to such materials. We demonstrate the formation of three-dimensionally continuous gyroidal mesoporous niobium nitride (NbN) superconductors from chiral ABC triblock terpolymer self-assembly-directed sol-gel-derived niobium oxide with subsequent thermal processing in air and ammonia gas. Superconducting materials exhibit a critical temperature (T c) of about 7 to 8 K, a flux exclusion of about 5% compared to a dense NbN solid, and an estimated critical current density (J c) of 440 A cm(-2) at 100 Oe and 2.5 K. We expect block copolymer self-assembly-directed mesoporous superconductors to provide interesting subjects for mesostructure-superconductivity correlation studies.
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Affiliation(s)
- Spencer W. Robbins
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
| | - Peter A. Beaucage
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Hiroaki Sai
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Kwan Wee Tan
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Jörg G. Werner
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
| | - James P. Sethna
- Department of Physics, Cornell University, Ithaca, NY 14853, USA
| | - Francis J. DiSalvo
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA
| | - Sol M. Gruner
- Department of Physics, Cornell University, Ithaca, NY 14853, USA
- Cornell High Energy Synchrotron Source, Cornell University, Ithaca, NY 14853, USA
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, NY 14853, USA
| | - Robert B. Van Dover
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Ulrich Wiesner
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA
- Corresponding author. E-mail:
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32
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Affiliation(s)
- Dong Gon Park
- Department of Chemistry; Sookmyung Women's University; Seoul 140-742 South Korea
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry; Cornell University; Ithaca NY 14853-1301 USA
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33
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Reckeweg O, Wakabayashi RH, DiSalvo FJ, Schulz A, Schneck C, Schleid T. About alkali metal dicyanamides: syntheses, single-crystal structure determination, DSC/TG and vibrational spectra of KCs[N(CN) 2] 2 and NaRb 2[N(CN) 2] 3 · H 2O. Zeitschrift für Naturforschung B 2015. [DOI: 10.1515/znb-2015-0056] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Transparent colorless crystals of KCs[N(CN)2]2 and NaRb2[N(CN)2]3 · H2O were obtained by blending aqueous solutions of Na[N(CN)2] and RbF or KF, respectively. After evaporation of the water, the remaining solid was extracted with absolute ethanol and the solvent was allowed to evaporate at r. t.. KCs[N(CN)2]2 crystallizes in the space group C2/c (no. 15) with the cell parameters a = 1382.7(2), b = 998.1(1) and c = 1455.4(2) pm, and β = 118.085(4) °. The structure of NaRb2[N(CN)2]3 · H2O is exhibiting the space group P63/m (no. 176) with the cell parameters a = 705.98(7) and c = 1462.89(12) pm. Single-crystalline α-K[N(CN)2] was obtained while attempting to synthesize ‘NaK2[N(CN)2]3’, corroborating the results of previous X-ray powder diffraction experiments. Vibrational spectra and DSC/TGA analyses complete our results.
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Affiliation(s)
| | - Ryo H. Wakabayashi
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
| | - Armin Schulz
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - Christof Schneck
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Thomas Schleid
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
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34
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Abstract
Molybdenum and tungsten diselenide are among the most robust and efficient semiconductor materials for photoelectrochemistry, but they have seen limited use for integrated solar energy storage systems. Herein, we report that n-type WSe2 photoelectrodes can facilitate unassisted aqueous HI electrolysis to H2(g) and HI3(aq) when placed in contact with a platinum counter electrode and illuminated by simulated sunlight. Even in strongly acidic electrolyte, the photoelectrodes are robust and operate very near their maximum power point. We have rationalized this behavior by characterizing the n-WSe2|HI/HI3 half cell, the Pt|HI/H2||HI3/HI|Pt full cell, and the n-WSe2 band-edge positions. Importantly, specific interactions between the n-WSe2 surface and aqueous iodide significantly shift the semiconductor's flatband potential and allow for unassisted HI electrolysis. These findings exemplify the important role of interfacial chemical reactivity in influencing the energetics of semiconductor-liquid junctions and the resulting device performance.
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Affiliation(s)
- James R McKone
- Department of Chemistry and Chemical Biology, Cornell University, 245 East Avenue, Ithaca, NY 14850, USA.
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35
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Reckeweg O, Schulz A, DiSalvo FJ. Synthesis, single-crystal structure determination and Raman spectrum of Cu[C(CN)3]2·2 NH3. Zeitschrift für Naturforschung B 2015. [DOI: 10.1515/znb-2014-0242] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Transparent, light blue crystals of Cu[C(CN)3]2·2 NH3 were obtained by dissolving Cu[C(CN)3]2 in aqueous ammonia and subsequent evaporation of the solvent under ambient conditions. Cu[C(CN)3]2·2 NH3 crystallizes in the space group C2/c (no. 15, Z = 4) with the cell parameters a = 1291.9(3), b = 753.18(15) and c = 1200.8(2) pm, and β = 92.68(3)°. The nature of the tricyanomethanide anion and the ammonia molecules were verified by Raman spectroscopy. Single crystals of Ag[C(CN)3] and Cu[C(CN)3]2 were synthesized, the known structures were confirmed and their Raman spectra were recorded for the first time for comparison.
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
| | - Armin Schulz
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
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36
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Reckeweg O, DiSalvo FJ. Two lithium tricyanomethanide compounds: syntheses and single-crystal structure determination of LiK[C(CN)3]2 and Li[C(CN)3]·½ (H3C)2CO. Zeitschrift für Naturforschung B 2015. [DOI: 10.1515/znb-2014-0250] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The new compounds LiK[C(CN)3]2 and Li[C(CN)3]·½ (H3C)2CO were synthesized and their crystal structures were determined. Li[C(CN)3]·½ (H3C)2CO crystallizes in the orthorhombic space group Ima2 (no. 46) with the cell parameters a=794.97(14), b=1165.1(2) and c=1485.4(3) pm, while LiK[C(CN)3]2 adopts the monoclinic space group P21/c (no. 14) with the cell parameters a=1265.7(2), b=1068.0(2) and c=778.36(12) pm and the angle β=95.775(7)°. Single crystals of K[C(CN)3] were also acquired, and the crystal structure was refined more precisely than before corroborating earlier results.
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
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37
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Reckeweg O, Schulz A, DiSalvo FJ. Syntheses, single-crystal structure determination, and Raman spectra of Rb[C(CN)3] and Cs[C(CN)3]. Zeitschrift für Naturforschung B 2015. [DOI: 10.1515/znb-2014-0241] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Extracting residues of an aqueous solutions containing equimolar amounts of K[C(CN)3] and RbF or CsF, respectively, with absolute ethanol, yields triangular, transparent colorless crystals of Rb[C(CN)3] and Cs[C(CN)3] after the ethanol was allowed to evaporate. The compounds are isotypic and crystallize isopointal to calcite in space group R3̅c (no. 167) with the cell parameters a=809.9(1) and c=1461.3(3) pm and a=843.29(9) and c=1459.9(2) pm, respectively. Single crystals were used to record the Raman spectra of the title compounds.
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
| | - Armin Schulz
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569 Stuttgart, Germany
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
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38
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Abstract
A facile synthesis of single-phase, nanocrystalline macroporous chromium nitride and chromium titanium nitride with inverse opal morphology is developed.
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Affiliation(s)
- Weitian Zhao
- Powder Technology Laboratory (LTP)
- École Polytechnique Fédérale de Lausanne (EPFL)
- Lausanne
- Switzerland
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39
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Tan KW, Sai H, Robbins SW, Werner JG, Hoheisel TN, Hesse SA, Beaucage PA, DiSalvo FJ, Gruner SM, Murtagh M, Wiesner U. Ordered mesoporous crystalline aluminas from self-assembly of ABC triblock terpolymer–butanol–alumina sols. RSC Adv 2015. [DOI: 10.1039/c5ra07421e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
One-pot synthesis of periodically mesostructured γ-alumina using an ABC triblock terpolymer as structure-directing agent and in situ derived rigid carbon scaffold.
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Affiliation(s)
- Kwan Wee Tan
- Department of Materials Science and Engineering
- Cornell University
- Ithaca
- USA
| | - Hiroaki Sai
- Department of Materials Science and Engineering
- Cornell University
- Ithaca
- USA
| | - Spencer W. Robbins
- Department of Materials Science and Engineering
- Cornell University
- Ithaca
- USA
- Department of Chemistry and Chemical Biology
| | - Jörg G. Werner
- Department of Materials Science and Engineering
- Cornell University
- Ithaca
- USA
- Department of Chemistry and Chemical Biology
| | - Tobias N. Hoheisel
- Department of Materials Science and Engineering
- Cornell University
- Ithaca
- USA
| | - Sarah A. Hesse
- Department of Materials Science and Engineering
- Cornell University
- Ithaca
- USA
- Department of Chemistry and Chemical Biology
| | - Peter A. Beaucage
- Department of Materials Science and Engineering
- Cornell University
- Ithaca
- USA
| | | | - Sol M. Gruner
- Department of Physics
- Cornell University
- Ithaca
- USA
- Cornell High Energy Synchrotron Source
| | - Martin Murtagh
- Department of Materials Science and Engineering
- Cornell University
- Ithaca
- USA
| | - Ulrich Wiesner
- Department of Materials Science and Engineering
- Cornell University
- Ithaca
- USA
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40
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Cui Z, Yang M, Chen H, Zhao M, DiSalvo FJ. Mesoporous TiN as a noncarbon support of Ag-rich PtAg nanoalloy catalysts for oxygen reduction reaction in alkaline media. ChemSusChem 2014; 7:3356-3361. [PMID: 25320003 DOI: 10.1002/cssc.201402726] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Revised: 09/09/2014] [Indexed: 06/04/2023]
Abstract
There has been growing interest in noncarbon supports for fuel cell reactions, especially for the oxygen reduction reaction (ORR) in alkaline media. Herein, we report a robust mesoporous titanium nitride (TiN) which is not only kinetically stable in alkaline media, but also electrochemically stable in the potential range of fuel cell operation. This binary nitride exhibits an order of magnitude higher electronic conductivity than carbon black. Bimetallic Ag-rich PtAg nanoalloy is selected as the catalyst for the ORR in alkaline media due to their superior activity and relatively low cost. TiN-supported Pt1 Ag9 nanoalloy catalysts are synthesized by a new and efficient approach with KEt3 BH as reducing agent and THF as solvent. Pt1 Ag9 /TiN exhibits much higher mass activity and durability for the ORR in alkaline media than Pt1 Ag9 /C, Pt/C and Ag/C catalysts, suggesting that mesoporous TiN is a very promising support in alkaline media.
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Affiliation(s)
- Zhiming Cui
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853 (USA).
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41
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Abstract
Mesoporous transition metal nitrides are interesting materials for energy conversion and storage applications due to their conductivity and durability. We present ordered mixed titanium-niobium (8:2, 1:1) nitrides with gyroidal network structures synthesized from triblock terpolymer structure-directed mixed oxides. The materials retain both macroscopic integrity and mesoscale ordering despite heat treatment up to 600 °C, without a rigid carbon framework as a support. Furthermore, the gyroidal lattice parameters were varied by changing polymer molar mass. This synthesis strategy may prove useful in generating a variety of monolithic ordered mesoporous mixed oxides and nitrides for electrode and catalyst materials.
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Affiliation(s)
- Spencer W. Robbins
- Department of Chemistry and Chemical Biology, Department of Materials Science and Engineering, Department of Physics, Cornell High Energy Synchrotron Source (CHESS), and Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Hiroaki Sai
- Department of Chemistry and Chemical Biology, Department of Materials Science and Engineering, Department of Physics, Cornell High Energy Synchrotron Source (CHESS), and Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Francis J. DiSalvo
- Department of Chemistry and Chemical Biology, Department of Materials Science and Engineering, Department of Physics, Cornell High Energy Synchrotron Source (CHESS), and Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Sol M. Gruner
- Department of Chemistry and Chemical Biology, Department of Materials Science and Engineering, Department of Physics, Cornell High Energy Synchrotron Source (CHESS), and Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Ulrich Wiesner
- Department of Chemistry and Chemical Biology, Department of Materials Science and Engineering, Department of Physics, Cornell High Energy Synchrotron Source (CHESS), and Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
- Address correspondence to
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42
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Cui Z, Chen H, Zhao M, Marshall D, Yu Y, Abruña H, DiSalvo FJ. Synthesis of structurally ordered Pt3Ti and Pt3V nanoparticles as methanol oxidation catalysts. J Am Chem Soc 2014; 136:10206-9. [PMID: 25000137 DOI: 10.1021/ja504573a] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Structurally ordered Pt3Ti or Pt3V intermetallic nanoparticle catalysts with ultrasmall particle sizes have never been successfully synthesized. Herein, we present a KCl-nanoparticle method to successfully provide such compounds. These two catalysts show enhanced catalytic activity and stability for methanol oxidation compared to pure Pt.
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Affiliation(s)
- Zhiming Cui
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853-1301, United States
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43
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Cui Z, Yang M, DiSalvo FJ. Mesoporous Ti(0.5)Cr(0.5)N supported PdAg nanoalloy as highly active and stable catalysts for the electro-oxidation of formic acid and methanol. ACS Nano 2014; 8:6106-6113. [PMID: 24836603 DOI: 10.1021/nn5014337] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We report a robust noncarbon Ti0.5Cr0.5N support synthesized by an efficient solid-solid phase separation method. This ternary nitride exhibits highly porous, sintered, and random network structure with a crystallite size of 20-40 nm, resulting in a high specific surface area. It is not only kinetically stable in both acid and alkaline media, but also electrochemically stable in the potential range of fuel cell operation. Two typical anode reactions, formic acid oxidation in acid media and methanol oxidation in alkaline media, are employed to investigate the possibility of Ti0.5Cr0.5N as an alternative to carbon. Bimetallic PdAg nanoparticles (∼4 nm) act as anode catalysts for the two anode reactions. PdAg/Ti0.5Cr0.5N exhibits much higher mass activity and durability for the two reactions than PdAg/C and Pd/C catalyst, suggesting that mesoporous Ti0.5Cr0.5N is a very promising support in both acid and alkaline media.
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Affiliation(s)
- Zhiming Cui
- Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14850, United States
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44
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Niepmann D, Pöttgen R, Poduska KM, DiSalvo FJ, Trill H, Mosel BD. Structure and Properties of the Stannides CeAuSn, Ce3Rh4Sn13, and Ce3Ir4Sn13. Zeitschrift für Naturforschung B 2014. [DOI: 10.1515/znb-2001-0102] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
CeAuSn, Ce3Rh4Sn13, and Ce3lr4Sn13 were prepared by reaction of the elements in an arc-melting furnace and subsequent annealing at 970 K for two weeks. The three stannides were investigated by X-ray powder and single crystal techniques. CeAuSn crystallizes with the NdPtSb type, space group P63mc: a = 472.7(2), c = 771.6(3) pm, wR2 = 0.0230,208 F2 values, 11 variable parameters, and BASF = 0.40(2). The gold and tin atoms form a pronounced two-dimensional [AuSn] polyanion which consists of slightly puckered Au3Sn3 hexagons. ,19Sn Mössbauer data at 78 K show one signal at an isomer shift of δ = 1.90(7) mm/s subjected to unresolved quadrupole splitting of ΔEQ = 0.55(2) mm/s. Ce3Rh4Sn13 and Ce3lr4Sn13 adopt the cubic Yb3Rh4Sn13 type structure, space group Pm3n: a = 970.51(3) pm, wR2 = 0.0721, 267 F2 values (Ce3Rh4Sn13) and a = 972.29(6) pm, wR2 = 0.0850, 267 F2 values (Ce3lr4Sn13) with 14 variable parameters for each refinement. Striking structural motifs in Ce3Rh4Sn13 are condensed distorted trigonal [RhSn6] prisms with Rh-Sn distances of 266 pm. The polyhedral network leaves two different cages which are occupied by cerium (6c position) and tin (2a position) atoms. The Sn2 atoms show occupancy parameters of only 92% (Ce3Rh4Sn13) and 76% (Ce3Ir4Sn13) and an extremely large displacement parameter indicating a rattling of these atoms within the icosahedral Sn12 cages. Magnetic susceptibility measurements of Ce3Rh4Sn13 show paramagnetic behavior down to 2 K with an experimental magnetic moment of 2.45(2) μB/Ce. No magnetic ordering is observed. Magnetization measurements show a moment of 0.78(2) μB/Ce at 2 K and 5.5 T. Resistivity data reveal only a very weak temperature dependence. The two crystallographically different tin sites are resolved in the 119Sn Mössbauer spectrum which shows a signal at δ = 2.12(1) mm/s subject to quadrupole splitting of 1.54(1) mm/s, superimposed by a singlet at δ = 2.47(1) mm/s. The Seebeck coefficient of Ce3Rh4Sn13 is within a few μ V/K of zero over the temperature range of 10 - 300 K.
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Affiliation(s)
- Dirk Niepmann
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13 (Haus D), 81377 München, Germany
| | - Rainer Pöttgen
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13 (Haus D), 81377 München, Germany
| | - Kristin M. Poduska
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, NY 14853, USA
| | - Francis J. DiSalvo
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, NY 14853, USA
| | - Henning Trill
- Institut für Physikalische Chemie, Universität Münster, Schloßplatz 4/7, 48149 Münster, Germany
| | - Bernd D. Mosel
- Institut für Physikalische Chemie, Universität Münster, Schloßplatz 4/7, 48149 Münster, Germany
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45
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Reckeweg O, Molstad JC, Levy S, Hoch C, DiSalvo FJ. Syntheses and Crystal Structures of Sr7H12X2 (X = Cl, Br). Zeitschrift für Naturforschung B 2014. [DOI: 10.1515/znb-2008-0506] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Dichroic, pink to blue single crystals of Sr7H12Cl2 and Sr7H12Br2 were obtained by reacting Sr with SrX2 or NaX and NaNH2 or NH4X (X = Cl, Br) as hydrogen sources in a Na melt at 900 °C for 12 h in silica-jacketed stainless-steel or Ta ampoules. The crystal structures of the new compounds were determined by means of single crystal X-ray diffraction. Both title compounds crystallize isotypically to Ba7Cl2F12 in the hexagonal space group P6̅ (no. 174) with the lattice parameters a = 998.06(3), c = 392.84(3) pm for Sr7H12Cl2 and a = 1004.62(3), c = 399.68(3) pm for Sr7H12Br2. The hydride positions taken from the difference Fourier map agree with those of the fluorides of the isotypic compound Ba7F12Cl12. The validity of our structural results is corroborated by EUTAX calculations and the comparison to SrH2, SrX2 and SrHX.
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
| | - Jay C. Molstad
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
| | - Scott Levy
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
| | - Constantin Hoch
- Max-Planck-Institut für Festkörperforschung, Heisenbergstr. 1, D-70569 Stuttgart, Germany
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
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Reckeweg O, DiSalvo FJ. Syntheses and Crystal Structures of the Solid Solution Sr4OBr2.89(2)Cl3.11(2) and the Elusive Ba2OBr2. Zeitschrift für Naturforschung B 2014. [DOI: 10.1515/znb-2011-1004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Transparent and colorless single crystals of the compounds Sr4OBr2.89(2)Cl3.11(2) and Ba2OBr2 were obtained by solid-state reactions of SrCl2, SrBr2 and SrO (3 : 3 : 2 molar ratio) or by using an excess of BaO together with BaBr2 and Ba as a flux with the molar ratio 3 : 2 : 2, respectively. Ba2OBr2 crystals are isopointal to K2ZnO2 adopting the orthorhombic space group Ibam (no. 72, Z = 4) with the cell parameters a = 7247.44(10), b = 1297.76(20) and c = 657.43(10) pm. Sr4OBr2.89(2)Cl3.11(2) is isotypic to Ba4OCl6 (or isopointal to K6ZnO4) and crystallizes in the hexagonal space group P63mc (no. 186, Z = 2) with the cell parameters a = 982.20(4) and c = 750.41(7) pm.
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, U. S. A
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, U. S. A
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Abstract
Abstract
Red-orange, transparent single crystals of Yb2[CN2]3 [trigonal, R3̄c (no. 167), a = 630.02(3) and c = 2947.4(2) pm, Z = 6] are obtained by the reaction of Yb, Sn, Zn[CN2] and NaN3 in arc-welded Nb ampoules at 1100 K. The title compound exhibits characteristic C-N bond lengths and angles [d(C-N) = 122.7(3) pm and ∡(N-C-N) = 178.4(5)°, respectively] within the [N=C=N]2− unit as well as the expected fundamental frequencies in its optical spectra (Raman: νs = 1338; δ = 643 / 683 / 695 cm−1; IR: νas = 2005 / 2037; δ = 640 / 679 cm−1). Since Yb2[CN2]3 adopts a corundum-type structure, Yb3+ is octahedrally coordinated by six N atoms of different [CN2]2− anions [d(Yb-N) = 228.6(3) and 233.4(3) pm, 3× each] and every [CN2]2− group has four Yb3+ as next neighbours which form a distorted tetrahedron.
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, U.S.A
| | - Thomas Schleid
- Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, U.S.A
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Reckeweg O, Molstad JC, Levy S, DiSalvo FJ. Syntheses and Crystal Structures of the New Ternary Barium Halide Hydrides Ba2H3X (X = Cl or Br). Zeitschrift für Naturforschung B 2014. [DOI: 10.1515/znb-2007-0104] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Single crystals of the isotypic hydrides Ba2H3X (X = Cl or Br) were obtained by solid-state reactions of Ba, NaCl, NaNH2 and metallic Na, or Ba, NH4Br and Na, respectively, in sealed, silicajacketed stainless-steel ampoules. The crystal structures of the new compounds were determined by means of single crystal X-ray diffraction. Ba2H3Cl and Ba2H3Br crystallize in a stuffed anti CdI2 structure and adopt the space group P3̄m1 (No. 164) with the lattice parameters a = 443.00(6), c = 723.00(14) pm and a = 444.92(4), c = 754.48(14) pm, respectively. The hydride positions are derived by crystallographic reasoning and with the help of EUTAX calculations. The results are compared with known data for binary and ternary alkaline earth metal hydrides.
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
| | - Jay C. Molstad
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
| | - Scott Levy
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
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Reckeweg O, Schulz A, DiSalvo FJ. Orthoborate Halides with the Formula (M+II)5(BO3)3X: Syntheses, Crystal Structures and Raman Spectra of Eu5(BO3)3Cl and Ba5(BO3)3X (X = Cl, Br). ACTA ACUST UNITED AC 2014. [DOI: 10.1515/znb-2011-0404] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Single crystals of Eu5(BO3)3Cl were obtained by serendipity by reacting Eu2O3 and Mg with B2O3 at 1300 K in the presence of an NaCl melt for 13 h in silica-jacketed Nb ampoules. Ba5(BO3)3X (X = Cl, Br) crystals were formed by direct synthesis from appropriate amounts of Ba(OH)2, H3BO3 and the respective barium halide (hydrate) in alumina crucibles kept in the open atmosphere at 1300 K for 13 h. The crystal structures of the title compounds were determined with single-crystal X-ray diffraction. All compounds crystallize isotypically to Sr5(BO3)3Cl in the orthorhombic space group C2221 (no. 20, Z = 4) with the lattice parameters a = 1000.34(7), b = 1419.00(9), c = 739.48(5) pm for Eu5(BO3)3Cl, a = 1045.49(5), b = 1487.89(8), c = 787.01(4) pm for Ba5(BO3)3Cl, and a = 1048.76(7), b = 1481.13(9) and c = 801.22(5) pm for Ba5(BO3)3Br. The Raman spectra of all compounds were acquired and are presented and compared to literature data. The incremental volume of the orthoborate (BO3)3− anion has been determined and is compared to the Biltz volume
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
| | - Armin Schulz
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
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Abstract
Single crystals of the compounds Ca4OCl6, Sr4OBr6, Ba4OBr6, and Ba2OI2 were obtained by solid-state reactions. The crystals of Ba2OI2 are transparent and colorless and isopointal to K2ZnO2 adopting the orthorhombic space group Ibam (no. 72, Z = 4) with the cell parameters a = 747.20(9), b = 1392.02(18), and c = 678.12(9) pm. Sr4OBr6 and Ba4OBr6 are isotypic to Ba4OCl6 (or isopointal to K6ZnO4) and crystallize in the hexagonal space group P63mc (no. 186, Z = 2) exhibiting the cell parameters a = 982.20(4) and c = 750.41(7) pm for Sr4OBr6 and a = 1030.10(2) and c = 785.92(4) pm for Ba4OBr6. In the ternary systems Ca-O-X (X = Cl, Br or I) the only compound found other than the starting materials was the already known Ca4OCl6 which is also isotypic to Ba4OCl6 crystallizing in the hexagonal space group P63mc (no. 186, Z = 2) with the cell parameters a = 903.30(6) and c = 683.27(8) pm.
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Affiliation(s)
- Olaf Reckeweg
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
| | - Francis J. DiSalvo
- Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301, USA
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